Modular skid frame with shear member

ABSTRACT

A modular skid frame and device to reduce the potential for harm and injury from arc flashes. The modular skid frame comprises a plurality of frame members secured together to form the skid frame, and one or more hook members formed on one or more of the frame members to permit the receipt of a bucket or blade from a loader, scoop tram or other construction or mining equipment into the bowl portion and behind the bill portion of the hook member to facilitate the lifting and moving of the skid frame. Also disclosed is a device for racking a circuit breaker into and out of a circuit breaker cradle. The device comprises an actuator operatively connected to the circuit breaker cradle to permit the circuit breaker to be racked into and out of the cradle without direct or indirect contact on the part of an operator.

FIELD OF THE INVENTION

This invention relates generally to modular skid frames of the type thatmay be used to house electrical components such as switch gear,transformers, motor controls, load centers, fused and unfuseddisconnects, breakers, electrical bus and the like. In another aspectthe invention relates generally to the field of reducing arc flashhazards.

BACKGROUND OF THE INVENTION

Skid frames for housing electrical components have been used in themining, exploration, oil and gas, and construction industries, and ingeneral industry, for a considerable length of time. Typically, suchskid frames include one or more of a variety of different electricalcomponents that perform various functions as may be required at aparticular application.

Skid frames as described above are generally constructed in a robustfashion from high strength material, such as steel, a steel alloy or acomposite, in order to withstand the relatively harsh environments inwhich they will be called upon to operate. As their name suggests, theytypically take the shape of a “frame” into which various components maybe installed. The frames are typically mounted upon skids or runnersthat allow them to be easily pushed or dragged from location to locationDepending upon the equipment installed in them, skid frames used inmining, exploration, oil and gas, construction and industrialapplications can cost from tens of thousands of dollars up to severalhundred thousand dollars each. It will be therefore be appreciated thatany effort that can be made to help to minimize their potential damageduring use will be advantageous to their owners.

In numerous applications skid frames containing load centers, fuseddisconnects, breakers and similar components are situation withinpotentially dangerous environments where there may be the presence ofexplosive or ignitable gases or dust particles. Such environments notonly include mining and oil and gas applications, but also numerousindustrial, construction and manufacturing facilities. Under conditionsof this nature the potential for an arc flash that can occur during theoperation of electrical equipment is of significant concern. Typically,arc flashes occur during the operation of electrical equipment such asdrawing out or closing a circuit breaker, opening or closing anelectrical device, or as a result of an insulation failure on electricalwires or systems. In situations where people are in close proximity tothe equipment that it is being operated, arc flashes can presentsignificant safety concerns, and in some cases have resulted in severeinjury and death.

One of the most common interactions between humans and electricalcomponents that can result in arc flashes is the racking in and out of acircuit breaker. In an effort to help minimize potential injury, othershave proposed attempting to isolate breakers in sealed cabinets toprevent their exposure to potentially explosive gases and dustparticles. However, even in cases where operators employ diligence andconduct routine and scheduled maintenance of their equipment, over timefasteners, gaskets and structural designs deteriorate making itdifficult, at best, to eliminate the potential danger to human safetyand life caused by arc flashes. It can also be extremely difficult tolocate issues or potential issues that may compromise the arc flashresistance of equipment.

Accordingly, there is a need for the continued development of modularelectrical skid frames having an enhanced ability to achieve a longereffective operating life. There is also a need to minimize the potentialfor injury or death associated with arc flashes that result from theoperation of electrical equipment, and in particular circuit breakers,either within modular skid frames or situated elsewhere.

SUMMARY OF THE INVENTION

The invention therefore provides a new and improved modular skid framethat provides for the potential for an increased effective operatinglife through utilization of a novel mechanism to permit the skid frameto be lifted and moved through the use of front end loaders, scoop tramsand the like without causing significant damage to the skid frame. Theinvention also provides for a new and novel mechanism to permit thejoining of adjacent modular skid frames, of the same or differentconfiguration, while accommodating shear loading between them. In thefurther embodiment the invention provides for a modular skid frame thatincludes a transformer having dampening means that cushions thetransformer in both a horizontal and vertical orientation to accommodatevibration and movement of the transformer, particularly when changingthe orientation of the skid frame from a generally horizontal to agenerally vertical position. In yet a further aspect the invention,provides a device for opening and closing a circuit breaker withoutdirect or indirect contact by an operator in order to reduce thepotential for injury or death of the operator on account of arc flash.

The invention therefore provides a new and novel modular skid frame, amechanism to join modular skid frames and a device for racking in andracking out a circuit breaker and the like that reduces the potentialfor injury or death of an operator on account of arc flash.

Accordingly, in one of its aspects the invention provides a modular skidframe comprising a plurality of frame members secured together to formsaid skid frame; and one or more hook members formed on one or more ofsaid frame members such that said hook members do not extend laterallyoutwardly from said frame members, said hook members comprised of adownwardly oriented bill portion and upwardly oriented bowl portion,said bowl portion extending vertically upwardly and laterally behindsaid bill portion, said bowl portion opening into the surroundingenvironment vertically beneath said bill portion, said one or more hookmembers permitting the receipt of a bucket or blade from a loader, scooptram or other construction or mining equipment into said bowl portionand behind said bill portion to facilitate the lifting and moving ofsaid skid frame.

In a further aspect the invention concerns a modular skid framecomprising a plurality of frame members secured together to form saidskid frame; a pair of coupling plates on at least: one end of said skidframe, said coupling plates assisting in releasably securing saidmodular skid frame to an adjacent modular skid frame of the same or adifferent configuration; one or more first tubular members extendingbetween said coupling plates; and, an elongate shear member receivedwithin one of said first tubular members when said skid frame isreleasably secured to an adjacent modular skid frame, the ends of saidelongate shear member rigidly secured to opposite side of said adjacentmodular skid frame, said elongate shear member, in conjunction with saidfirst tubular member through which it is received, assisting in thesecurement of said modular skid frame to said adjacent modular skidframe and helping to accommodate shear loading between said respectivemodular skid frames.

The invention also provides a device for racking a circuit breaker intoand out of a circuit breaker cradle, the device comprising actuatingmeans operatively secured, directly or indirectly, to the circuitbreaker cradle, said actuating means having an engaged and a disengagedposition and being movable between said engaged and said disengagedpositions, when moving from said disengaged to said engaged positionsaid actuating means causing the circuit breaker to be racked or drawninto the cradle, when moving from said engaged to said disengagedposition said actuating means drawing or racking the circuit breaker outfrom the cradle, said actuating means operable such that movementbetween said engaged and said disengaged positions is accomplishedwithout direct or indirect contact by an operator.

In still a further embodiment the invention provides a device forracking a circuit breaker into and out of a circuit breaker cradle, thedevice comprising an actuator operatively connected to the circuitbreaker cradle, said actuator movable between an engaged and adisengaged position such that moving said actuator from said disengagedto said engaged position causes the circuit breaker to be racked intothe cradle and moving said actuator from said engaged to said disengagedposition causes the circuit breaker to be racked out of the cradle, saidactuator operably connected to a remote controlling system such thatsaid actuator is movable between said engaged and disengaged positionsthrough operation of said remote controlling system permitting saidcircuit breaker to be racked in and racked out without direct orindirect contact on the part of an operator.

Further aspects and advantages of the invention become apparent from thefollowing description taken together with the accompanying drawings.

DESCRIPTION OF THE DRAWINGS

For a better understanding of the present invention, and to show moreclearly how it may be carried into effect, reference will now be made,by way of example, to the accompanying drawings which show the preferredembodiments of the present invention in which:

FIG. 1 is an upper side perspective view of a modular skid frame made inaccordance with one of the preferred embodiments of the presentinvention;

FIG. 2 is a partial front view of the modular skid frame shown it FIG.1;

FIG. 3 is a partially exploded enlarged perspective view of the enddetail of the modular skid frame shown in FIG. 1;

FIG. 4 is a sectional view taken along the line 4-4 of FIG. 3;

FIG. 5 is a upper side perspective view of a circuit breaker cradleincorporating a device for racking in and racking out a circuit breakerin accordance with one of the preferred embodiments of the presentinvention;

FIG. 6 is a side perspective view of the circuit breaker cradle shown inFIG. 5 incorporating an alternate embodiment of the device for rackingin and racking out the circuit breaker;

FIG. 7 is a side perspective view of the circuit breaker cradle shown inFIG. 5 incorporating a further alternate embodiment of the device forracking in and racking out the circuit breaker;

FIG. 8 is a side perspective view of the circuit breaker cradle shown inFIG. 5 incorporating yet a further alternate embodiment of the devicefor racking in and racking out the circuit breaker;

FIG. 9 is a side view of the circuit breaker cradle having securedthereto an embodiment of a device for racking in and racking out thecircuit breaker in accordance with one of the preferred embodiments ofthe invention wherein the breaker is in a racked in position;

FIG. 10 is a front view of the circuit breaker cradle shown in FIG. 9;

FIG. 11 is a side view of the circuit breaker cradle shown in FIG. 9wherein the breaker is in a racked out position;

FIG. 12 is a front view of the circuit breaker cradle shown in FIG. 11;

FIG. 13 is an exploded view of device for racking in and racking out acircuit breaker as shown in FIG. 7;

FIG. 14 is an exploded view of the device for racking in and racking outa circuit breaker as shown in FIG. 6;

FIG. 15 is an exploded view of a modular skid frame made in accordancewith one of the preferred embodiments of the present inventionillustrating the electrical switching and control modules that may bereceived therein;

FIG. 16 is an upper front perspective view of a circuit breaker modulethat may be received within one embodiment of the modular skid frame;and

FIG. 17 is an upper rear perspective view of the circuit breaker moduleshown in FIG. 16.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention may be embodied in a number of different forms.However, the specification and drawings that follow describe anddisclose only some of the specific forms of the invention and are notintended to limit the scope of the invention as defined in the claimsthat follow herein.

With reference to FIG. 1, a modular skid frame constructed in accordancewith one of the preferred embodiments of the present invention is notedgenerally by reference number 1. Skid frame 1 is comprised generally ofa plurality of frame members 2 which would in most cases be constructedof a high strength material, such a as steel, a steel alloy or acomposite. Depending up the particular application, the frame membersmay be subjected to hardening or heat treating processes, may bepainted, coated for corrosion resistance, or have any one of a widevariety of other treatments applied to them. Typically the frame memberswould be assembled in a fashion to form one or more semi-enclosedcompartments 3 designed to house particular equipment or structures. Inso doing the frame members are most often arranged in a box-like mannerwith end frames sections, bottom frame sections, upper or top framesections, and in some cases intermediary walls. The upper surface (orroof) of the skid frame will be commonly be enclosed to protectcontained equipment. One or more skid rails 4 extend along the bottomframe section to act as runners to help facilitate dragging or pushingthe skid frame from place to place.

in the embodiment of the skid frame shown in the attached drawings, theframe members include a pair of coupling plates 5 positioned on at leastone end (but preferably both ends) of the skid frame. As will bedescribed in further detail below, the coupling plates assist inreleasably securing one skid frame section to an adjacent modular skidframe section that may be of an identical or a different configuration.Coupling numbers 5 have one or more first tubular members 6 extendinglaterally between them. in the embodiment shown in the drawings, twosuch tubular members are shown extending laterally across the end of theskid frame and between the coupling plates. Typically the couplingplates that extend outwardly from one end of the skid frame would befitted with tubular members 6, while the coupling plates of the oppositeend would not thereby forming, in general terms, male and female ends onthe modular skid frame. In this manner, when it is desired to secure twoskid frame modules together end to end, the male end of one skid framecan be received within the female end of a second skid frame such thatthe coupling plates of the two skid frames modules nestle and can bebolted together.

With reference to FIGS. 3 and 4, when joining two modular skid frames(of the nature of those described above), together in an end to endrelationship elongate shear members 7 are received within the firsttubular members on the male end of the first skid frame. To accomplishthis the coupling plates on the adjacent female end of the second skidframe will contain holes that line up with tubular members 6 on thefirst skid frame to permit the insertion of shear members 7. The ends ofthe elongate shear members have flanges 8 attached to them that in turnrigidly secure the shear members to the coupling plates of the femaleend of the adjacent skid frame. Preferably the cross-sectional shape ofthe elongate shear members closely match the hollow interior of thetubular members such that there is a relatively close tolerance betweenthe parts when they are assembled together.

In most instances it is expected that the first tubular member andelongate shear members will be comprised of high strength pipe, with thepipe the forming elongate shear members closely fitting within internaldiameter of the pipe forming the tubular members (see FIG. 4). It willbe appreciated that in this manner when fully assembled the elongateshear member 7, in conjunction with the tubular member 6 through whichis received, will not only assist in the securement of the two skidframes together, but will help to accommodate :shear loading between therespective modular skid frames. In the embodiment of the invention shownin the attached drawings, there are two such tubular members, shearmember structures positioned at each end of the skid frame. It will,however, be understood that one or more such tubular members could beutilized.

Referring to FIGS. 1, 2 and 3, one embodiment the modular skid frameincludes one or more hook members 9 formed on one or more of the framemembers 2. Hook members 9 are preferably recessed into the frame memberssuch that they do not extend laterally outwardly from the frame membersand thus do not impede the placing of the skid frame up against anobject or wall, and to also help to minimize the risk that the hockmembers will catch on other objects, devices or equipment. Hook members9 are comprised generally of a downwardly oriented bill portion 10 andan upwardly oriented bowl portion 11. As shown in FIGS. 1, 2 and 3 thebowl portion extends in a generally vertical direction upwardly andlaterally behind the bill portion. The bowl portion has a mouth thatopens into the environment vertically beneath the lower tip of the billportion to effectively create an undercut structure behind the bill.Such a structure permits the receipt of a bucket or blade from a loader,scoop tram or similar piece of construction or mining equipment intobowl 11 and behind bill 10 of hook member 9 in order to facilitate thelifting and moving of the skid frame.

From an examination of FIG. 1 it will he appreciate that placing thefront lip of a bucket into the hook members on the end of skid frame 1will enable the bucket to be received behind the bill portions and in sodoing permit the end of the skid frame to he lifted so that the entireframe can easily be shifted in a lateral direction (left to right).Receipt of the bucket into the hooks and behind bills 10 will also allowthe skid frame to be dragged or pushed to a desired location withoutdamaging frame members 2. in the embodiment shown, hook members 9 areformed in coupling plates 5 and will thus be made. from a high strengthsteel, steel alloy or a composite. For larger skid frames, an additionallayer of material may be attached to the sides of coupling plates 5 atthe point where the hook members are formed in order to increase thestrength and rigidity of the hooks (see FIG. 3).

To help prevent flexing and torsional strain being applied to the skidframe when it is lifted or moved by means of hook members 9, couplingplates 5 may be positioned vertically along the outer ends of the skidframe, with each coupling plate each haying a hook member 9 formedtherein. In this manner a bucket received within the hook members willtend to lift, pull or push the skid frame by points of contact on theframe's corner members which will be of high structural integrity andwhich, due to their spacing apart, will help to reduce the tendency totwist or apply torsional loading to the frame. As shown in FIG. 2, thefact that hook members 9 do not extend laterally outwardly from theframe members means that the hook members do not interfere with theability of the skid frame to be pushed up tightly against an adjacentskid frame thereby facilitating the joining of the two modules together.Securing two adjacent modules together can thus be accomplished throughbolting their respective coupling plates together, through the use ofelongate shear members received within first tubular members asdiscussed above, and through the use of coupling bars 12 that wouldtypically be received within the bottom frame members.

It will also be appreciated that through the provision of one or morededicated hook members 9 that are specifically designed to assist in thelifting and movement of the modular skid frame from place to place therewill be a tendency to reduce damage that may otherwise be cause to theskid from through traditional manners of moving the skid frame, Commonlyskid frames are moved through ramming a piece of equipment up against itin order to push or drag it into position. The use of specific anddedicated hook members will encourage operators to refrain from pushingagainst other frame members of the skid frame which may not have thesame level of structural integrity of hook embers 9 and coupling plates5. Thus the described structure will have a tendency to reduce thepotential for damage being caused to the skid frame, which will in turnhelp to increase its useful life and reduce the need and cost formaintenance,

FIG. 1 further shows an embodiment of the invention wherein modular skidframe 1 includes a transformer 13 (in this case 3 transformers mountedon a single base plate 14) that is secured either directly or indirectlyto one or more of the frame members within the skid frame. That is, thetransformer may be secured directly to the frame members or,alternatively, the transformer may be equipped with its own frame andmounting structure that is in turn secured to the skid frame. In thisembodiment of the invention the transformer includes both vertically andhorizontally oriented dampening means 15 that serve to both cushion thetransformer and to help reduce vibration that is transmitted to itduring movement of the skid frame. In the embodiment shown, thedampening means comprise spring dampening means 16, however, it will beappreciated that other forms of dampening means including hydraulic andpneumatic cylinders could equally be utilized. The dampening means mayalso include base insulators. Through using both vertical and horizontaldampening means, the skid frame enables the transformer to be isolated,to a certain degree, from vibration and the effects of impact hat canoccur when the skid frame is moved around. In mining, construction andother applications, modular skid frames such as those described hereinare often moved by large heavy equipment and can be subjected tosignificant and violent forces. Further, in some instances the skidframes are lifted, tilted or even placed in a vertical orientation whenbeing moved from place to place. The use of both vertical and horizontaldampening means to cushion and protect a transformer can thus reducedamage to it, increase its use for lifespan and potentially reduce theneed and cost of maintenance procedures.

In accordance with a further embodiment of the invention there isprovided a device for racking in and racking out a circuit breaker. Itwill be appreciated by those of ordinary skill in the art that rackingin (drawing in) a circuit breaker into its cradle will result in amechanical connection of the breaker's current carrying stabs withcurrent carrying members of the cradle. Similarly racking out thebreaker will disengage the breaker's current carrying stabs from currentcarrying members of the cradle.

in FIGS. 5 through 14 such a device is shown generically through the useof reference number 17. Device 17 comprises an actuating means oractuator 18 that is mounted exterior to a circuit breaker cradle 19. Theactuating means is movable between an engaged and a disengaged positionsuch that when it moves from its disengaged to its engaged position theactuating means causes a circuit breaker 50 to be racked into cradle 19.Similarly, when actuating means 18 moves from its engaged to itsdisengaged position the actuating means draws out or racks out breaker50. In this manner, operation of actuating means 18 causes circuitbreaker 50 to be either racked in or racked out, accordingly. As will bedescribed in more detail below, in accordance with this aspect of theinvention the actuating means is operable such that it may be movedbetween its engaged and disengaged positions without direct or indirectcontact by an operator. FIGS. 5, 6, 7 and 8 show four of the manydifferent potential configurations of actuating means that could beutilized accordance with preferred embodiments of the present invention.It will be appreciated by those of ordinary skill in the art that forillustration purposes a particular form of circuit breaker cradle 19 hasbeen shown, however, the invention is not limited to its applicationupon such cradles only and the invention may be applied to any of a wideof variety of circuit breaker cradles, it should also be appreciatedthat depending upon the nature of the cradle in question, theenvironment within which it is mounted, and also the nature of actuatingmeans 18, device 17 may also be operatively secured to an enclosure orframe upon which the cradle is mounted. The actuating means may beelectrically, hydraulically or pneumatically powered.

Of significant importance to device 17 is the fact that actuating means18 is controlled remotely such that moving the actuating means betweenits engaged and disengaged positions can be accomplished without thepresence of an operator in the vicinity of circuit breaker 50. Theelectrical, hydraulic or pneumatic powering of actuating means 18presents the ability for device 17 to be controlled in a remote operatoror control station which may be in a secure and safe location either inthe same general vicinity as the breaker or, alternatively, in acompletely different area of a construction site, a centralized locationin an of or gas field or plant, or in the case of an underground minemay be potentially be located at the surface. Control may also bethrough a wired or wireless network and could include the option ofremotely controlling equipment by means of a portable computer, smartphone or smart PDA.

Regardless of the particular location of the operator, the importantfactor is that he or she will be located a safe distance from circuitbreaker 50 such that when it is racked out or racked in any arcing thatmay occur and any subsequent arc flash, while potentially damagingsurrounding equipment, will not inflict harm upon personnel. Through useof device 17, personnel do not have to approach the equipment to operateit and can safely stay beyond the arc flash boundary. This presents asignificant advantage over existing cradles and actuating systems thatto one extent or another require an operator to be in either physicalcontact with the breaker and cradle, or to be within close proximity. Insituations where long telescopic poles are used to rack in and rack outcircuit breakers, such poles still have a practical limit to theirlength, after which they become unmanageable. Even the longest polesthat can be handled by an operator require that operator to berelatively close to the circuit breaker. If the breaker is situated inan environment that contains explosive gases or dust particles, anyarcing could result in a flash that ignites a sufficient amount of gasor dust, particles to engulf the operator. It is for such reasons thatoperators in some instances are required by law, or by practicesestablished by management, to wear protective suits and head gear whenengaged in such tasks. Completely removing the operator from harm's wayin such circumstances therefore presents a significant advancement overexisting technologies.

The remote operation of device 17 also presents the ability toincorporate a wide variety of different sensors and monitoringmechanisms either in or around the vicinity of circuit breaker 50. Forexample, sensors can be incorporated into the breaker to feed signals tothe control station to indicate whether the breaker is in an open or aclosed configuration and whether the breaker is racked in or racked out.In addition, sensors could be incorporated in or around the breaker orits cabinet to detect the nature of the surrounding environment (i.e.the presence of methane or other explosive gases or dust particles).Thermal sensors could be utilized to indicate breaker and/or busstemperature to signal an overheating situation. In some applications itmay also be desirable to include lights and video cameras in which casereal-time, streaming video could be sent to an operator's console tovisually display the condition of the breaker and its surroundingcomponents, Where the overheating of the breaker or other components maybe of particular concern an infra-red camera could be utilized toprovide a heat signature of the breaker, the actuating means and variousother related or connected equipment or components,

Referring again to FIGS. 6 through 8, in FIG. 6 the embodiment ofactuating means 18 that is shown comprises an actuator 20 in the form ofan electric gear drive having its shaft operatively connected to cradle19 to permit the breaker to be racked in and racked out . FIG. 7 showsan alternate embodiment of a similar gear drive actuator, whereas theembodiment shown in FIG. 8 depicts the use of a linear actuator 21 thatis connected to a drive box 22 that is turn operatively connected to thecradle 19.

FIGS. 9 through 12 show schematically a circuit breaker in a racked inand a racked out configuration. In these particular figures actuatingmeans 18 is comprised of a pair of linear actuators, one situated oneach side of the circuit breaker cradle 19. It will be appreciated thatdepending upon the particular breaker and cradle in question, and theconfiguration of the breaker and cradle, one, two or more actuators maybe necessary in order to rack in and rack out the breaker or,alternatively, may be desirable in terms of an efficient operation or interms of built in redundancy.

In accordance with a further aspect of the invention, actuating means 18includes a manual override 23 to allow for the manual racking in andracking out of breaker 50. Depending upon the particular configurationof the actuating means and its actuator, manual override 23 may take oneof a variety of different forms. In the embodiments shown in theenclosed drawings, manual override 23 is a drive shaft coupling 24 thatis connected to drive box 22. The drive shaft coupling permits anoperator to utilize either a manual handle or an electrically operateddrive mechanism that may be connected to the drive box to manually torack the breaker in or out. Manually racking the breaker in or out maybe necessary or convenient in particular instances, such as when allpower going to the breaker has been disconnected and there is no chanceof an arc flash occurrence. Manual override 23 also permits the rackingout of the breaker 19 in certain emergency situations when for onereason or another actuating means 18 may not be functional.

FIGS. 13 and 14 show exploded views of two forms of actuating means thatmay comprise device 17 for racking the breaker in and out. In FIG. 13there is shown an actuating means 18 that is comprised generally of anactuator 20 and a drive box 22. The drive box contains a shaft 28 thatis connected to the breaker mechanism (which includes the cradle). Thedrive box may in some cases also include a speed reducer (could be aworm gear reducer other form of speed reducer) having a shaft 25 that isconnected to a motor 26 by way of a gear box 27. In FIG. 13 the motor isan electric motor, however, it may also be in some instances a hydraulicmotor or a pneumatic power source. It will thus be appreciated thatoperation of the motor will result in the rotation of drive shaft 25,which will in turn result in the rotation of shaft 28 that will causethe breaker to be racked in or racked out, depending on the direction ofrotation of motor 26.

A mechanically equivalent structure for actuator 20 to that as shown inFIG. 13 is depicted in FIG. 14. Here the actuator is comprised of alinear actuator 21, however, it could equally be an electric solenoid, ahydraulic or pneumatic cylinder or any other such or similar device. Thelinear actuator, at its upper end, is fitted with a bracket 29 thatsecures the actuator to the enclosure or frame to which circuit breakercradle 19 is mounted. The opposite end of the actuator is connected toshaft 28 of drive box 22 through the use of a drive yolk 30. Operationof the actuator will thus cause shaft 28 to be rotated in either aclockwise or a counter-clockwise direction to cause the breaker to beeither racked in or out, Due to the nature of the linear actuator, themanual racking in or out of the breaker will typically require thedecoupling of the actuator from the drive yolk through removal of pin31. In other embodiments the actuator may be coupled to the yolk throughthe use of other releasably securable fastening means.

It will thus be appreciated that through the use of device 17, thebreaker may be racked in and racked out in a manner that helps to ensurethe safety of personnel and that limits their exposure to arc flashes.The control system to which device 17 is connected (which may includePLC's and/or other micro processor controls and computers) permits notonly the racking in and out of a breaker, but also provides for themonitoring of a wide range of system parameters and environmentalfactors. The control system may be programmed to automatically rack outthe breaker in certain circumstances where a danger to personnel orequipment may be present, however, where there is an insufficientelectrical issue to cause the breaker to trip. For example, it may bedesirable to connect fire detection systems and sensors to the controlsystem for the actuating means that automatically cause the breaker tobe racked out in the event that a fire is detected. Previously, undersuch circumstances there would have to be a significant breach of anelectrical system for the breaker to trip or, alternatively, an operatorwould have to physically go to the breaker cabinet and manually open thebreaker or rack the breaker out using traditional means.

From a thorough understanding of the structure and function of device 17it will be understood that the device may be utilized on breakers andbreaker cradles that may be employed in any one of a very wide varietyof different applications, For example while reference has been made touse of device 17 in association with mining applications it couldequally be used in surface plants, manufacturing facilities, oil and gasproduction sites, general commercial applications, constructionapplications, etc. The nature of device 17 is such that its usefulnessand function is not limited to use on breakers that control anyparticular load or piece of equipment. Further, while in the embodimentsof the invention shown in the attached drawings device 17 is depicted asbeing exterior to cradle 19, it will be appreciated that it could alsobe constructed so as to be an internal component situated within orinside the cradle.

It will also be appreciated that device 17 may be incorporated into acircuit breaker module 32 that may be received within modular skid frame1. The breaker module would typically be connected to a bus bar withinthe skid frame to help reduce arc flash probability outside ofsituations where the breaker is racked in or racked out. The nature ofmodule 32 and skid frame 1 is such that modules like those showngenerally in the drawings and noted generally by reference numeral 32are essentially plug-and-play modules that can be inserted into definedcompartments within skid frame 1, allowing the skid frame to beconfigured as desired for any particular application. That is, in mostinstances modules 32 will be of one or more defined exterior dimensionsso that different forms of modules (for example different breaker sizes,fused disconnects, control equipment, relays, etc) can be easilyinserted and mounted within the skid frame. The plug-and-play nature ofmodules 32 also has a tendency to help minimize electrical wiring errorsat site. The internal wiring of the modules can be completed moreefficiently and with a greater degree of accuracy in an assembly plant,after which the fully wired and assembled modules can be shipped andinserted into a desired compartment within the skid frame. The varioussensors and other monitoring equipment described above can also in mostinstances be pre-mounted within module 32. Doing so further reduces thelikelihood of wiring errors on site and allows the sensors to beconnected to a remote operating or control system through simplyconnecting a data cable on module 32 into a pre-existing port situatedwithin the skid frame.

Since in most instances the functionality of the breaker cradle or otherequipment housed within module 32 will be remotely controlled, themodule will preferably have a fixed access door or cover having sealsabout its peripheral edge to help prevent the ingress of explosivegases, dust particles, moisture, etc. To ensure that. equipment isinoperable while access doors or covers are open, electrical interlocksmay be utilized to prevent the closing of switches and breakers whiledoors and/or covers of module 32 are either open or have been removed.Once again, as in the case of the other sensing devices describedpreviously, if desired the status of the covers or doors of module 32can be displayed remotely at the operator or control station.

It is to be understood that what has been described are the preferredembodiments of the invention and that it may be possible to makevariations to these embodiments while staying within the broad scope ofthe invention. Some of these variations have been discussed while otherswill be readily apparent to those skilled in the art.

1-22. (canceled)
 23. modular skid frame comprising: (i) a plurality offrame members secured together to form said skid frame; (ii) a pair ofcoupling plates on at least one end of said skid frame, said couplingplates assisting in releasably securing said modular skid frame to anadjacent modular skid frame of the same or a different configuration;(iii) one or more first tubular members extending between said couplingplates; and, (iv) an elongate shear member received within one of saidfirst tubular members when said skid frame is releasably secured to anadjacent modular skid frame, the ends of said elongate shear memberrigidly secured to opposite sides of said adjacent modular skid frame,said elongate shear member, in conjunction with said first tubularmember through which it is received, assisting in the securement of saidmodular skid frame to said adjacent modular skid frame and helping toaccommodate shear loading between said respective modular skid frames.24. The modular skid frame as claimed in claim 23 wherein said framemembers form one or more semi-enclosed compartments.
 25. The modularskid frame as claimed in claim 23 including a bottom frame section, saidbottom frame section including one or more skid rails.
 26. The modularskid frame as claimed in claim 23 wherein hook members are formed insaid coupling plates.
 27. The modular skid frame as claimed in claim 23having two first tubular members extending between said coupling plates,each of said first tubular members having received therein an elongateshear member, said first tubular members with said elongate shearmembers received therein together helping to accommodate shear loadingbetween said respective modular skid frames.
 28. The modular skid frameas claimed in claim 23 including an electrical transformer secureddirectly or indirectly to one or more of said frame members, saidelectrical transformer including both vertically and horizontallyoriented dampening means, said dampening means cushioning saidtransformer and helping to reduce vibration transmitted to saidtransformer during movement of said skid frame or upon changing theorientation of said skid frame from a generally horizontal to agenerally vertical position.
 29. The modular skid frame as claimed inclaim 23 wherein said dampening means comprises spring dampening means.30. The modular skid frame as claimed in claim 23 including one or morehook members formed on one or more of said frame members such that saidhook members do not extend laterally outwardly from said frame members,said hook members comprised of a downwardly oriented bill portion andupwardly oriented bowl portion, said bowl portion extending verticallyupwardly and laterally behind said bill portion, said bowl portionopening into the surrounding environment vertically beneath said billportion, said one or more hook members permitting the receipt of abucket or blade from a loader, scoop tram or other construction ormining equipment into said bowl portion and behind said bill portion tofacilitate the lifting and moving of said skid frame.